Devices for emitting electromagnetic radiation are known in diverse configurations. Corresponding devices can be used for a variety of purposes.
By way of example, such a device can be used as a radiation source for spectroscopic purposes. In particular, absorption measurements for determining a concentration of a substance contained in a fluid can be carried out thereby. The correlation—described by Lambert's and Beer's law—between the concentration of a substance that is contained in a fluid and absorbs electromagnetic radiation and the change in the intensity of electromagnetic radiation upon passing through the fluid contained the absorbing substance allows a relatively simple determination of the concentration of a substance contained in a fluid.
A conventional device for emitting electromagnetic radiation that is used for such spectroscopic measurements generally comprises an optical semiconductor element in the form of a light-emitting diode. An emission characteristic, in particular the intensity and distribution, of a light-emitting diode is not temporally and spatially constant over the operating time of the light-emitting diode and is dependent on a multiplicity of ambient conditions.